Liquid door check



` A 2 sheetssheet 1. J. H. SHAW. Y

LIQUID DOOR CHECK.'

QNo Model.)

' 2 Sheets-Sheet 2.

J. H. SHAW.

LIQUID D001. CHBGK..`

Patented June 4, 1895.

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III"

UNITED STATES VP*r1-:NT OFFICE.

JOHN H. SHAW, OF NEW HAVEN, CONNECTICUT, ASSIGNOR TO THE SARGENT da COMPANY,..OFSAME PLACE.

' LIQUID DOOR-CHECK.

SPECIFICATION forming part of Letters Patent No.f540,518, dated June 4,1895. Aopiiootion noa November 26,1394. soria No. 529,971. (No modi-,1.)

To all whom t may concern: which match into corresponding threads Be it known that I, JOHN H. SHAW, of New formed in the cylinder, which is constructed Haven,in the county of New Haven andState with anannular shoulder a, upon which the of Connecticut, haveinvented anew Improvediaphragm rests. AThe said diaphragm di- 55 5 ment in Fluid Door-Checks; andI do hereby vides the cylinder into a fluid-chamber C, declare the following, when taken in connecwhich is located below it, and into a spring tion with the accompanying drawings and the chamber C', which is located above it. letters of reference marked thereon, to be a Within the Huid-chamber C, I locate a verfull, clear, and exact description of the same, tically and rotatably movable plunger D, hav- 6c 1o and which said drawings constitute part of ing a smooth periphery, which works directly this specification, and represent, inagainst the smooth inner walls of the cham- Figure l, a plan view of one form which a ber, the joint between which and the plunger door-check constructed in accordance with is as close as can be made without interfermyinvention may assume; Fig. 2,afullsizedI ing with the free movement of the latter. 65 I5 view, in vertical section, on the line a b of The upper face of the plunger is' provided Fig. l; Fig. 3, a detached View, in Vertical with an integral centrally arranged couplingcentral section, of the case or cylinder of the 'head D', having two corresponding parallel check, the same being shown on the same Working faces D2 D2, andacentrally threaded scale as Fig. l; Fig. 4, a broken View, invertiopening D3, which passes down through the 7o 2o cal section, on the scale `of Fig.2, but on the body of the plunger. A threaded post E, re-

line c d of Fig.o1, and showing the ports, valveduced at its upper and lower ends to form chamber, and valve of the device; Fig. 5, -a .bearings E and E2, is located in an upright detached view of the valve; Fig. 6,a detached position in the center of the duid-chamber, View of the plunger; Fig. 7, a detached reand passes through the centrally threaded 75 25 verse plan view of the spindle, only the yoke opening D2, formed in the plunger and. the thereof being shown; Fig. 8, a broken View, coupling-head thereof, as described, the in side elevation, of the spindle and plunger; Vthreads of the post matching into those of the Fig. 9, a View of the casein rear elevation on Opening. The bearing E2 formed at the lower v the scale of Figs. l and 3; Fig. 10, a view in end of the post is set into a depending step 8o 3o horizontal section on line e f of Fig. 9. A2, formed integral withthe bottom of ther My invention relates to an improvement in Casing. Within the said step I locate a key fluid door-checks, which are that class of e, which enters a vertical slot formed in the checks in which a fluid is employed to secure said bearing for holding the post against rothe soft closing of the door to resist the power tation. 'The reduced bearing E formed at 8 5 3 5 of the door-spring, the object being to prothe upper end of the said threaded post, en-

duce a durable and effective device, composed ters a socket F, formed in a yoke F', located of few parts, and not liable to derangement, within the uid chamber C, and made inteand adapted to be converted for use on doors gral with the inner end of the spindle F2. opening to the right or left. The said yoke has two corresponding coup- 9o 4o With these ends in view, my invention conling members F2F2, having parallel operating sists in a fluid door-check having certain defaces F4 F4, corresponding in their separation tailsofconstruction and combinations ofparts to the separation of the faces D2 D2 of the as will be hereinafter described, and pointed coupling-head of the plunger, the sai'd faces out in the claims. of the coupling-head and yoke being adapted 95 45 In carrying out my invention, as herein in width to cover the movement of the plun- Vshown, I employa heavy cylinder or case A, ger up and downin the Huid chamber, as will adapted, in the usual manner to be applied be set forth later on. Between .the spindle to a door, having its lower .end closed, and its F2 and the yoke F', there is formed a bearing upper end furnished with aremovable cap Af. collar F5, which is integral with them, and roo 5o Within this cylinder I locateahorizontal diawhich has bearing in a central opening B phragm B,having external peripheral threads, formed in the diaphragm B.

It will be understood that within the fiuid-` chamber C, I by preference locate some heavy liquid, such as glycerine, which in the operation of the check is transferred from one side of the plunger to the other, fiowing freely in one direction, and under restraintin the other, as will be set forth. For the free transference of the fluid from the upper to the lower end of the chamber, I form in the wall of the uuid-chamber two ports G and G', respectively located near the upper and lower ends of the chamber, and terminating at their outer ends iu a vertical valve-chamber G2, formed in an integral,verticall y arranged offset from the lower portion of the case A. In this chamber I locate a valve, comprising, as herein shown, a body I'I, furnished at its upper end with a slotted cylindrical head H', the slot h whereof is adapted to receive a screw-d river, by means of which the valve may be reversed in position, as required for converting the check for use on right and left hand doors. The body of the valve is cut away on its opposite faces, and constructed with a valve opening H2, through which the fluid passes in being transferred from one side of the plunger D, to the other. The said Valve also has apivoted sheetmetal iiap II, pivoted at its lower end, and bearing against one of the cut away faces of the body, so as to close the opening H2.

The valve shown and just described, is well adapted for use in my improved check, but I do not limit myself to its use` as it might b e replaced by other valves adapted to operate in the same or substantially the same way. I may here say that when the check is to be used in combination with a door opening to to the right, the valve is turned with its flap outward,whereby the fluid is permitted to fiow freely from the upper portion of the chamber into the lower portion thereof, and below the pluuger,which is elevated during the opening movement of the door, and occupies an elevated position at the beginning of the closing movement thereof. The passage of the fluid will be through the port G, into the valvechamber G2, then through the valve opening A2 into the lower portion of the valve-chamber, then through the port G into the iiuidchalnber. On the other hand, when the door to which the check is applied opens from left to right, the valve is turned so that its flap will be on the inside, and permit the fluid to t flow freely from the lower to the upper portion of the chamber, which is then unoccupied, because the opening of the door to the left will secure the depression of the piston, which will be depressed at the time the closing movement of' the door begins. When the valve is turned with its flap inward, as described,|the fiuid will flow from the lower end of the fluid-chamber into the port G', then into the lower portion ot' the valve-chamber, then through the opening H2 of the valve, into the upper portion of the valve chamber and then through the port Gr into the upper portion of the iiuid chamber. The return passage of the iiuid is controlled and takes place much more slowly, provision for it being made by forming a vent opening I, in the upper portion of the wall of the fluid-chamber, and a corresponding opening l in the lower portion of the wall ot' the said chamber, these openings terminating at their inner ends in a vent passage I2, formed in a vertically arranged integral projection I3, located upon the lower portion of the case, as clearly seen in Fig. 9. The virtual size of the vent passage I2, is controlled by means of a vent-plugJ,having a head J, fitted into the upper end of the passage, and constructed with a long stem J2, furnished at its upper end with an outwardly projecting handle J3, which extends above the top of the case A, in position to be readily manipulated by hand, so as to control the return passage of the fluid when the same is under the pressure of the plunger. The vent plug is cut away, as at j, and its positidh in the passage I3 determines the amount of fluid which may flow through the same. I will say,` however, that this vent plug may be varied in construction, or replaced by any other device, which will control the restrained passage of the fluid from one side of the plunger to the other. I conceive that both the valve and vent plug might be changed or omitted, without altering the essential operation of the plunger and spindle, as will be described later on.

vWithin the spring-chamber C, I locate a heavy spring K, the outer end of which is connected in the usual manner to the cap A' of the case, while its inner end is connected with a sleeve L, which forms a long bearing for the spindle F2, and which is provided at its upper end with a notched hub L bearing upon the central upwardly projecting boss a of the cap A. The said slotted hub is engaged by means of a pawl M pivotally secured to the lower face of the door-lever N, the inner end of which is set over the squared upper end of the spindle, which is thus virtually connected with the inner end ofthe spring through the medium of the said lever N, the pawl M, the hub L and the sleeve L. The inner end of the door-lever, I would observe, rests upon the upper face of the hub L,and is held down thereupon by means of a nut N. rlhe outer end of the door lever has connected with it an adjustable casing-leverO, the opposite end of which carries a bracket O', adapted to be connected with the casing of the door. I would have it understood, however, that I do not limit myself to any particular wayof connecting the door spring with the case or spindle, nor to the employment of any particular construction of door and casing-levers, as these devices are well known and may be varied.

Having thus described the construction of one form which adoor-check madein accordance with my invention may assume, I will proceed to set forth the mode of its operation. Assuming that the check is applied to a door opening from right toleft, the plunger D will be located in the bottom of the fluid chamber IIC' y'with the fluid above it, when the door is in its closed position. When now the door is opened, the spindle F2 will be rotated against the tension of the door spring K, whereby the yoke F at the lower end .of the spindle will be rotated, and cause the plunger to be rotated, and therefore lifted by the co-action of the threadswithin its coupling head with the threads of the fixed post standing upright in the fluid chamber. VThe sliding movement between the yoke and the coupling-head of the plunger permits the plunger to be lifted -without being disengaged from the spindle, at the same time the plunger is being spirally rotated. As the plunger rises, the fluid located above it escapes into the port G, and flows freely through the valve in the valvechamber G2, and emerges into the lower portion of the chamber at a point under the plunger. It will be understood that when the door is fully open, the plunger will be at its highest point. Now when the door begins its closing movement, the plunger will be depressed against the fluid in the lower portion of the chamber, and the said fluid will at once be put under considerable pressure, tending to force it back through the ports G and G into the upper portion of the chamber, but there is no passage for it in that direction, inasmuch as the flap H3 automatically closes and obstructs the flow of fluid, which is therefore forced to find another passage into the upper portion ofthe fluid chamber. The fluid, therefore, enters the vent opening I', and flows through the passage I2, past the vent plug J, and emerges into the upper portion of the fluid-chamber; but the passage last described is so small that thefluid ows very slowly, and inasmuch as the plunger cannot descend except as room is made for it by the discharge of fluid from the lower portion of the fluid-chamber, the closing movement of the door will be restrained and checked, for just in the proportion that the downward movement of the plunger is checked, so also is checked the rotation of the spindle Fwithout which there can be no movement of the door. The closing movement of the door will therefore be checked by the restrainedor controlled transference of the fluid from the lower to the upper portionof the fluid cham- Y ber, and that transference will be comparais made integral therewith. The strain therefore is wellv resisted, and the case is not liable to burst, and cannot leak.' It is conceived that there will be some little leakage of fluid between the plunger and the side walls of the duid-chamber and between the threads of the coupling head and threadedspost, but that leakage maybe compensated for,and will not Having fully described my invention, what l I claim as new, and desire to secure by Letters Patent, is-

1. In a fluid door-check, the combination with a case having a fluid chamber, of a plunger located therein, a non rotatable screwthreaded post located in the said chamber, and passing through the plunger which has threads matching into its threads, and means engaging with the plunger for rotating it whereby it is moved back and forth in the chamber through the medium of the post, substantially as described.

2. In a fluid door-check, the combination with a case containing a fluid-chamber, of a. longitudinally movable and rotatable plunger located in the said chamber, and constructed with an internally threaded coupling-head, a non-rotatable threaded post located in the said chamber, and passing through the internally threaded coupling-head of the plunger, and a spindle furnished with a yoke co-acting with the coupling-head of the plunger, and operat- Y ing when rotated to raise and lower the same, substantially as set forth.

3. In a. fluid door-check, the combination with a case containing a fluid chamber, of a longitudinally movable and rotatable threaded plunger located therein, a non-rotatable threaded post located in the said chamber and having its threads matched into those off the plunger, and a spindle constructed to engage with the plunger to rotate the same and cause it to move longitudinally in the chamber,

`through the medium of the threads upon the post, one end of which has bearing in a portion of the spindle and the other in the case, substantially as set forth. Y

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

JOHN I-I. SHAW'.

Witnesses:

JOHN SARGENT, WILLIAM S. CooKE.

IIO 

